Abstract

Greenhouse gas emissions from private motor vehicles are of significant policy interest in Australia and around the world. Technological efforts, such as introduction of more fuel efficient vehicles, may help the problem, but a consensus is slowly arising that the only way to make significant changes is to reduce the amount of travel being undertaken by the private car. Travel patterns are best viewed not as the result of openended choices, but rather a reflection of the constraints faced by individuals within our community. One of the greatest constraints faced is the environment within which we live, which for most Australians will be an urban (or suburban) environment. There is extensive literature to show that the nature of this urban environment (its "urban form") has a major impact on the travel patterns of its residents.

For this thesis, it was hypothesised that measurable features of urban form, that is to say, a city's population and employment distribution, design patterns and transport services, would have a systematic impact on the transport patterns of its residents. To test this hypothesis at the Australian suburban level, a range of new data was collected: household transport data for Sydney, Melbourne and Perth local government areas and corresponding urban form data. This included population density, job density, street layout, road supply and public transport service levels. The two sets of data were subjected to analysis using ordinary linear regression.

The analysis reveals a clear pattern. Inner city areas generate low VKT, and thus low emissions, and emissions per capita increase steadily as distance from CBD increases. Exurban areas generate significantly greater VKT, and within suburban areas proper, a combination of street layout and access to full-time public transport explains 75% of variance in private motorized VKT. A straight-forward model is produced and validated using a subset of recent data. Rather than directly influencing mode choice, a minimum density of population is identified as being necessary for the efficient operation of public transport, and further research in this area is indicated.